Instantly warp into any vehicle.

Kaneda Rides up walls

The kaneda bike you unlock from the ronin missions will drive all the way up the side of any building.
You need to face the wall and then backup far enough so when you go forward you can wheelie and have your front tire rest on the wall. Then give it gas.
If you just do a wheelie at the wall it wont work, you will just do a big burnout on the ground.
You need to get the timing right so you are just far enough away to be barely doing a wheelie when you hit the wall with the front tire.

Keep Cop Uniform

How to get:
Step 1 - Get a friend or someone to host a co-op game for you. Join them.
Step 2 - Start any Fuzz activity.
Step 3 - Fail the mission by killing the cameraman, or kill yourselves.
Step 4 - When the failed screen shows, tell the host to not press any buttons.
Step 5 - At the failed screen, YOU (not the host) press the back button to exit the game, and save.
Step 6 - Load your save and you should have the uniform. Sometimes you may not have the shirt, so you can go to Branded and get one. The badges and radio are stuck to your skin so it will be on whatever shirt you choose.
Step 7 - Save your outfit to keep it in your wardrobe.